Carriage drive for high-speed printer



Jan. 28, 1969 A. F. MARION CARRIAGE DRIVE FORHIGH-SPEED PRINTER- Filed Aug. 28, 1967 -//vv/v/2 ANDRE F. MARION 5y A? ATTORN Y United States Patent 2 Claims ABSTRACT OF THE DISCLOSURE This patent relates to high-speed printers and more particularly to a print carriage shifting mechanism therefor. The carriage, with a print hammer supported thereon, moves continuously relative to a print line on a recording medium, and carries with it a type-wheel on which a series of type characters is circumferentially arranged in a single helical tum. Continuous movement of the print carriage from right to left parallel to and transversely of the recording medium is under the control of a toothed belt having a running engagement with a pinion on the carriage. Normally, in the at rest position of the carriage, the pinion rotates freely with the continuous movement of the belt. However, upon initiation of a printing operation, an electromagnetic brake is energized and becomes effective to stop rotation of the pinion, thereby causing the carriage to move with the belt. Upon completion of a line of printing, the electromagnetic brake is de-energized and the carriage returns to its at rest position under the influence of a relatively strong spring.

High-speed printing machines for tabulating information such as that derived, for example, from a computer are well-known. Generally, such printers are either of two types, a successive character, or series, printer or a line printer. With the first type a line is printed characterby-character to its completion, at which time the print receiving medium or paper is line spaced and the next line of printing is begun. In the use of the second type or line printer, a complete line of characters is printed simultaneously.

The machine of the present invention is of the series type and utilizes a continuously moving carriage on which a single print hammer is supported. A type-wheel, on which a single series of type characters is circumferentially arranged in the form of a helix, is moved along concomitantly with the print hammer transversely of the line-by-line movement of the print receiving medium, the print receiving medium and an inking ribbon being disposed between the type hammer and type-wheel. The typewheel rotates continuously and for each revolution of the type-wheel, the axial movement thereof, together with the movement of the print hammer, is equivalent to the columnar spacing of the printing of the characters on the print receiving medium as determined by the pitch of the helix. In each columnar position of the type-wheel a signal is supplied by the computer or data processing system which selectively controls the actuation of the print hammer and the printing of a desired character.

In printing machines of the series type in use today, various methods are applied for controlling the movement of the print hammer or type-wheel or both conjointly along a printing line transversely of the print re ceiving medium. One such method is disclosed in Patent No. 2,926,602 issued to MacDonald et al., March 1, 1960, wherein the type-wheel is slidably keyed to a continuously rotating shaft which, during its rotation, applies tension to a steel hand against the action of a spring loaded drum, the steel band being connected to the type-wheel carriage, Another such method is the use of a continuously Patented Jan. 28, 1969 rotating helical shaft as described in the copending application of Andre F. Marion et al., Ser. No. 650,501.

SUMMARY OF THE INVENTION In a high-speed printing device having a continuously rotating type-wheel and a print hammer associated therewith, a continuously running endless toothed belt is enmeshed with a suitable pinion supported for normally free rotation on the type-wheel and print hammer transport means. Upon a command signal from a computer or other piece of data processing equipment, rotation of the pinion is stopped to connect the transport carrier with the belt and begin a line of printing. At the conclusion of the printing of a line, a second command signal releases the pinion for free running, whereupon the carriage returns to its at rest position.

It is therefore an object of the present invention to provide a high-speed printer with a simple and effective printing mechanism.

Another object of the present invention is to provide an improved drive mechanism for the printing carrier of a high-speed printer releasable upon completion of printing in any position in any line.

Other objects and advantages will be apparent from the following description of the preferred embodiment of the invention as illustrated in the accompanying drawings in which:

FIG. 1 is a fragmentary plan view of the printer showing the printing carrier drive mechanism;

FIG. 2 is a fragmentary sectional elevational view with a portion of the printing carrier broken away to show the brake for the carrier drive pinion, the view being taken on the plane indicated by line 22 in FIG. 1; and

FIG. 3 is a view of the print mechanism in perspective.

The invention is preferably shown as being embodied in a high-speed printing device of a well known type such as that disclosed in the application of Andre F. Marion et al., Ser. No. 650,501. The framework of the device includes a base upon which a pair of spaced upright parallel side-frames 11 and 12 are secured (FIG. 1). Journalled in the side-frames 11 and 12 is square shaft 14 (FIGS. 1, 2 and 3) which support the type-wheel 15 for axial sliding movement therealong.

In the embodiment shown, raised type characters 0 through 9 are arranged in a single helical turn on the periphery of the type-wheel 15. The hub of the typewheel 15 is rotatably engaged in the bifurcated upper end of the bracket 16 which is slidably supported on shaft 17 and serves to impart axial movement to the type-wheel along square shaft 14. Shaft 17 is secured at its respective ends in frame members 11 and 12 in axial parallel relationship to the square shaft 14. Movement of the typewheel 15 is coincident with that of the print hammer 18 rockably mounted at 19 on the print hammer carriage, generally indicated at 22, which is suitably supported on a pair of spaced axially parallel shafts 23 and 24 for sliding movement parallel to the axis of rotation of typewheel 15. Each of the shafts 23 and 24 is secured at its respective ends in frame members 11 and 12.

Upon sliding movement of the carriage 22 along shafts 23 and 24, a like movement is imparted to the typewheel 15 by means of cable 25. To this end, pulleys 26 and 27 are mounted for rotation on suitable pins on the flattened portion of the respective ends of the shaft 17. Similar pairs of pulleys 28 and 29 are independently rotatably supported on suitable pins on the flattened portion of the respective ends of shaft 30, which shaft is secured at its ends in frame members 11 and 12 in axial parallel relationship to shaft 17. Each end of the cable 25 is secured, by means of clamp 32, to the type-wheel carrier bracket 16, extending to the right thereof passing over pulley 27, thence over the lower of the pair of pulleys 29, thence over the upper of the two pulleys 28, returning to and passing over the upper of the pair of pulleys 29 to the lower of the pair of pulleys 28, thence passing over pulley 26 and returning to the left side of the typewheel carrier bracket 16. At a point intermediate its length, and between pulleys 28 and 29, the inner run of the cable 25 is secured to the print hammer carriage 22 by means of clamp 31. Thus, it can be seen that upon the movement of the carriage 22 in either direction, a similar and coincident directional and synchronous movement is imparted to the type-wheel 15.

The inking of the type-wheel 15 may be effected by an inking ribbon positiond between the print receiving medium P and the type-wheel 14, paralle to the axis of rotation of the wheel. On the other hand, the inking of the type-wheel may be effected by means of an inking roller, as disclosed in the aforementioned application Ser. No. 650,501. The print receiving medium or paper P is held in position, free of the .drum but adjacent thereto, by suitable means not shown. Upon completion of the printing of a line, paper P is line spaced to a position for printing of the next line. Such inking and line spacing means are well known and have not been shown since they form no part of the present invention. Normally, spring 36 resiliently retains print hammer 18 in spaced relationship to the type-wheel 15 to enable the movement of the paper P therebetween. To effect printing, the electromagnet 37, associated with print hammer 18, is energized, thereby causing the print hammer to press the paper P and the ink ribbon against a selected type character on the type-wheel 15 which is directly opposite. During each revolution of type-wheel 15, the wheel moves axially one columnar space and, while rotating continuously, any selected character on the type-wheel may be printed in each column on the paper P due to the helical arrangement of the type characters on the periphery of the wheel, as is well known. The columnar spacing corresponds to the pitch of the helix formed by the type characters on the type-wheel.

In order to move the print hammer carriage 22 and, therefore, type-wheel 15, an endless timing belt 40 is carried by each of two toothed pulleys 41 and 42 having a similar pitch diameter. Toothed pulley 41 is rotatably supported on a pin 43 secured on one leg of a right-angle bracket 44, the other leg of which is secured on frame member 12, with a portion of the pulley extending through a suitable aperture in the frame member. The other toothed pulley 42, which serves to drive belt 40, is secured on the upper end of a vertically disposed shaft 45, suitably journalled in the spaced parallel cars 46 and 47 of a bracket 48 secured on frame member 11. A portion of the toothed pulley 42 is disposed in and the belt 40 passes through a suitable aperture 49 in frame member 11. Continuous movement is imparted to belt 40 by means of beveled gears 55 and 56, beveled gear 55 being secured on shaft 45 and beveled gear 56, enmeshed therewith, being secured on the end of a shaft 57 of an electric motor, not shown, suitably supported on the base of the machine. Adjacent beveled gear 56, motor shaft 57 is journalled in one leg of a right-angle bracket 58 secured on frame member 11.

Movement of the print hammer carrier 22, as well as type-wheel 15, is selectively controlled by the continuously moving belt 40, the runs of which are disposed parallel to the axis of the carrier supporting shafts 23 and 24 and the axis of type-wheel shaft 14. For this purpose, a pinion 60 is constantly enmeshed with the teeth of the toothed belt 40 and is secured on a shaft 61 journalled in each of the horizontally disposed spaced parallel arms 62 and 63 of print hammer carrier 22. At its lower end, shaft 61 is extended below the arm 63 of the carrier 22 and carries a disc 64 secured thereto. A ring 65, preferably of a frictional material, such as fiber, is secured on the top face of the disc 64 concentric therewith. Normally, continuous movement of the toothed belt 40 imparts rotation to the pinion 60 and disc 64.

When it becomes desirable to connect the carrier 22 to belt 40 for movement thereby, rotation of the pinion 60 is terminated, so that by virtue of the engagement of the belt 40 with the pinion 60 and the clockwise rotation of the toothed pulley 42 (FIG. 1), the carrier 22 moves to the right, as viewed in FIG. 1. In order to stop rotation of the pinion 60, a frictional ring 66, identical to ring 65, is secured on an armature plate 67 of an electromagnet assembly 68 having an operating coil 69, ring 66 being concentric with ring 65. Armature 67 is in the form of a metal disc nonrotatably and freely mounted for up and down movement on four equiangularly arranged pins 70 secured in the arm 63 of carrier 22. Normally, armature disc 67 is resiliently retained against the lower surface of the arm 63 by means of relatively light compression springs 71 supported on the extended portion of pins 70 between the disc 67 and suitable clips 72 secured on the pins 70. In this position of the armature 67, ring 66 is spaced sufficientl from ring 65 to permit normally free rotation of pinion 60, the planar surfaces of the rings being substantially parallel. The electromagnet assembly 68 is carried by an offset bracket 73 secured on print hammer carrier 22 and, upon energization of the coil 69, becomes effective to attract the armature 67 downwardly to effect a pressure engagement of ring 66 with the ring 65 on disc 64. Thus, rotation of pinion 60 is immediately terminated thereby enabling the movement of the carriage 22 by the continuously moving belt 40.

As explained hereinbefore, with each revolution of the type-wheel 15 the carrier 22 moves one columnar space during the printing of each line and as a desired type character on the wheel reaches the print line, the coil 37 is energized to actuate print hammer 18, thereby causing the character to be printed on the print receiving medium P. Normally, the continuously moving toothed belt 40 causes pinion 60 to rotate freely without imparting motion to the print hammer carrier 22, However, to begin a line of printing, the coil 69 of the electromagnet assembly 68 is energized, in a well-known manner through the logic circuit of an arithmetic control unit (not shown), terminating rotation of the pinion 60 and thereby causing movement of the carrier 22 and the continuously rotating type-wheel 15 from left to right along a print line as viewed in FIG. 1. Upon completion of each line of printing at any columnar position in the line, coil 69 of the electromagnet 68 is deenergized releasing armature 67 to the influence of springs 71, whereby pinion 60 is released for rotation and spring 74, under tension, becomes immediately effective to return carrier 22 and typewheel 15 to the at rest position against stop pin 75 secured on frame 11. The operation of print hammer 18 and the energization and deenergization of the coil 69 of the electromagnet assembly 68 is under the control of command signals generated by suitable well-known logic and control circuits (not shown).

What is claimed is:

1. In a printing device having a continuously rotating type-wheel for printing on a print receiving medium:

a series of type characters arranged in a helix on the peripheral surface of said type-Wheel,

a type hammer including an actuator therefor adapted to cause said hammer to strike a selected character upon each revolution of said type-wheel,

a carrier means supporting said type hammer for movement in either direction transversely of the print receiving medium and parallel to a print line,

a support means for controlling movement of said type-wheel along its axis of rotation,

means connecting said support means to said carrier means for concomitant movement of said type-wheel with said type hammer,

a resilient means normally operable to retain said carrier means in an inactive position and effective to restore said carrier means following movement thereof in one direction from the inactive position, and

means operable to drive said carrier means for movement of said type hammer and type-wheel in said one direction an amount equal to the pitch of the helix with each revolution of the type-wheel, the combination comprising:

a continuously running endless toothed belt,

a shaft rotatably supported on said carrier,

a pinion secured on said shaft in normal running engagement with said belt,

a first brake member secured on said shaft normally rotatable by said pinion,

a plate nonrotatably supported in a normally inoperative position on said carrier parallel to the rotational plane of said first brake member and movable axially of said shaft relative to said first brake member,

a second brake member carried by said plate operable to frictionally engage said first brake member upon movement of said plate to the operative position,

spring means normally operable to resiliently maintain said plate and said second brake member parallel to the plane of rotation of and out of engagement with said first brake member, and

a signal responsive means for controlling movement of said plate to the operative position terminating rotation of said pinion to enable movement of said carrier in said one direction and for selectively enabling operation of said spring means and said resilient means following each of a plurality of revolutions of said type-wheel.

2. In a printing device having a continuously rotating type-wheel for printing on a print receiving medium:

a series of type characters arranged in a helix on the peripheral surface of said type-wheel,

a type hammer including an actuator therefor adapted to cause said hammer to strike a selected type character upon each revolution of said type-wheel,

a carrier means supporting said type hammer for movement in either direction transversely of the print receiving medium and parallel to a print line,

a support means for controlling movement of said type-Wheel along its axis of rotation,

means connecting said support means to said carried means for concomitant movement of said type-wheel with said type hammer,

a resilient means normally operable to retain said carrier means in an inactive position and eifective to restore said carrier means following movement thereof in one direction from the inactive position, and

means operable to drive said carrier means for movement of said type hammer and type-wheel in said one direction an amount equal to the pitch of the helix With each revolution of the type-wheel, the combination comprising:

a continuously running endless toothed belt,

a shaft rotata'bly supported on said carrier,

a pinion secured on said shaft in normal running engagement with said belt,

a first brake member secured on said shaft normally rotatable by said pinion,

an armature plate nonrotatably supported in a normally inoperative position on said carrier parallel to the rotational plane of said first brake member and movable axially of said shaft relative to said first brake member,

a second brake member carried by said armature plate operable to frictionally engage said first brake member upon movement of said armature to the operative position,

spring means normally operable to resiliently maintain said armature and said second brake member parallel to the plane of rotation of and out of engagement with said first brake member, and

an electromagnet signal responsive to effect movement of said armature to the operative position terminating rotation of said pinion and to selectively enable operation of said spring means following each of a plurality of revolutions of said type-wheel.

References Cited UNITED STATES PATENTS 434,391 8/1890 Hunter 188-163 XR 2,395,905 3/1946 Oetzel 188-161 2,698,679 3/1946 Vernhes 188-161 XR 2,843,243 7/1958 Masterson 101-93 XR 2,886,149 5/1959 Baerman 188-161 XR 2,926,602 3/1960 MacDonald et a1. 101-93 3,007,561 11/1961 Harting 188-161 XR 3,039,708 6/1962 Chidgey et al. 74-166 XR 3,135,195 6/1964 Potter 197-49 XR 3,261,431 7/1966 Kershner et a1 188-161 XR EDGAR S. BURR, Primary Examiner.

US. Cl. X.R. 

